List of quick balloon activities for children, Pre-K - K
See exercise, "Modeling States of Matter:" It's an excellent introduction to this concept for squirmy young kids! This might be improved by an activity where kids try going through an open carton or doorway, alone and in linked groups of two or more. This would demonstrate that larger molecules can't pass through openings as quickly, which relates to 1) how some scent molecules seem stronger than others and 2) how helium balloons deflate faster than those filled with air.
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